Publication-only abstracts (abstract number preceded by an "e"), published in conjunction with the 2019 ASCO Annual Meeting but not presented at the Meeting, can be found online only.
Lactate response during acute exercise in cancer survivors undergoing exercise rehabilitation.
Symptoms and Survivorship
2019 ASCO Annual Meeting
J Clin Oncol 37, 2019 (suppl; abstr e23047)
Author(s): Nicholas Harman, Arjun Ramani, Benjamin Jacob George, Reid Hayward; School of Sport and Exercise Science and the University of Northern Colorado Cancer Rehabilitation Institute, University of Northern Colorado, Greeley, CO; Banner MD Anderson Cancer Center, Greeley, CO
Background: Cancerous cells express a markedly different metabolic profile characterized by lactate production even when oxygen is plentiful. Lactate accumulation is a common marker for energy production and utilization, yet it is currently unclear how blood lactate responds during acute exercise to volitional fatigue in individuals with cancer and how this response is modified with exercise-based rehabilitation. The purpose of the current study is to assess the effect of an acute exercise bout to volitional fatigue on lactate accumulation before and after an exercise-based rehabilitation program for cancer survivors. Methods: 33 cancer survivors (female, n = 18; male, n = 15) were recruited to participate in a 12-week exercise-based rehabilitation program. All participants performed an initial assessment of physiological parameters, including blood lactate accumulation (LA) during a progressive treadmill protocol to volitional fatigue. LA was quantified every 2 minutes during treadmill testing via finger stick. The exercise intervention consisted of one hour sessions, three days per week, and included cardiovascular endurance, muscular strength, balance, and flexibility exercises. After 12 weeks of rehabilitation, participants completed a follow-up evaluation of physiological parameters. Results: There was a significant increase in LA at volitional fatigue after 12 weeks of training (Initial: 6.17 ± 2.61 mM, Post 12 Weeks: 7.26 ± 2.10 mM; p = 0.04), with no significant difference in resting blood lactate. The workload at which anaerobic lactate threshold presented was significantly increased after 12 weeks (Initial: 5.87 ± 1.59 METs, Post 12 weeks: 7.35 ± 1.85 METs; p = 0.02). Conclusions: Cancer survivors respond to acute exercise to volitional fatigue in a manner similar to healthy controls. Furthermore, similar to the response observed in healthy populations, cancer survivors exhibited an increase in lactate threshold and an increase in peak lactate accumulation at volitional fatigue after completing an exercise-based rehabilitation program. Thus, although many cancerous cells have a unique glycolytic profile, this does not appear to influence training-induced adaptations in blood lactate.